generate random password with special characters javascrtip

1function generatePassword(passwordLength) {
2  var numberChars = "0123456789";
3  var upperChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
4  var lowerChars = "abcdefghijklmnopqrstuvwxyz";
5  var allChars = numberChars + upperChars + lowerChars;
6  var randPasswordArray = Array(passwordLength);
7  randPasswordArray[0] = numberChars;
8  randPasswordArray[1] = upperChars;
9  randPasswordArray[2] = lowerChars;
10  randPasswordArray = randPasswordArray.fill(allChars, 3);
11  return shuffleArray(randPasswordArray.map(function(x) { return x[Math.floor(Math.random() * x.length)] })).join('');
12}
13
14function shuffleArray(array) {
15  for (var i = array.length - 1; i > 0; i--) {
16    var j = Math.floor(Math.random() * (i + 1));
17    var temp = array[i];
18    array[i] = array[j];
19    array[j] = temp;
20  }
21  return array;
22}
23
24alert(generatePassword(12));

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